Diabetic neuropathy (DN) and peripheral neuropathy (PN) are peripheral nervous system disorders, and these conditions constitute the most common complication of diabetes mellitus (DM). In the United States, around 23.6 million children and adults have diabetes, which is around 8% of the entire population. Approximately 60% of those with long-standing diabetes are affected by neuropathy.
Diabetic and peripheral neuropathy causes loss of sensation in various parts of the body, particularly the lower extremities. In addition, people with neuropathy have reduced quality of life due to chronic pain, as well as wounds that are difficult to heal. Neuropathy also affects sensory, motor, and autonomic nerve fibers, causing a burning, searing pain.
What are stem cells?
Stem cells are cells in the body that are undifferentiated biological cells. These cells can convert into specialized cells and divide through mitosis to create more stem cells. These cells are found in the bone marrow, adipose (fat) tissue, and amniotic fluid. The adult stem cells are used to treat muscle and nerve problems.
Adult stem cells are multipotent undifferentiated cells taken from bone marrow, adipose tissue, or amniotic fluid. These cells have anti-inflammatory properties, which are useful in providing pain relief and enhance wound healing. These stem cells also have self-renewability properties and possess a safety level better than embryonic stem cells.
How do stem cells work?
Bone marrow-derived mesenchymal stem cells (MSCs) secrete various cytokines that support neurological and angiogenic effects. These cells provide the cellular microenvironment that supports hematopoiesis. They are easy to obtain and have been show to differentiate into multi-lineage cell types. Because of these actions, stem cells are useful for treating diabetic and peripheral neuropathies.
In a recent study, MSC transplantation was effective for treating diabetic neuropathy in rat subjects. After a month following the transplantation, certain products of the stem cells were noted in muscle fibers. These cells are thought to have therapeutic effects on neuropathy through paracrine actions of growth factors, which are secreted by the MSCs.
Can bone-marrow derived cells treat vascular problems?
Bone-marrow progenitor cells help with various vascular conditions. Vasculogenesis is the development of blood vessels from endotheilial progenitor cells, which change into endotheilial cells. In addition, angiogenesis involves growth of pre-existing vasculature, through migration and proliferation of endothelial cells. These bone-marrow derived cells can be used to repair damaged blood vessels through vasculogenesis and angiogenesis.
What does the research show?
Recent studies show that differentiation of the bone-marrow cells into endothelial lineage cells will repair damaged vessel walls. The study showed that the bone-marrow derived cells increased endothelia cell differentiation in hind limb muscles, which increased blood flow. The bone-marrow obtained cells had a direct effect on peripheral nerves.
In another study, lab rats with diabetes were injected with MSCs. The researchers found that these cells could attenuate or reverse experimental neuropathy by modulation of angiogenesis and restoration of myelin, which surrounds the nerves. In a study involving people, 10 participants with symptoms of nerve pain had liposuction to obtain MSCs. Of these individuals, pain outcomes greatly reduced at 6-month follow-up. The researchers found that administration of stem cells significantly reduced neuropathic pain.
Han JW, Sin MY, & Yoon Y (2013). Cell Therapy for Diabetic Neuropathy Using Adult Stem or Progenitor Cells. Diabetes Metab Jornal, 37(2), 91-105.
Han JW, Choi D, Lee MY, et al. (2014). Bone marrow-derived mesenchymal stem cells improve diabetic neuropathy by direct modulation of both angiogenesis and myelination in peripheral nerves. Cell Transplant.
Vickers ER, Karsten E, Flood J, & Lilischkis R (2014). A preliminary report on stem cell therapy for neuropathic pain in humans. J Pain Res, 7, 255-263.